This invention is directed to an oxidizing composition, a method of oxidizing waste materials in a moving substantially aqueous stream, and a kit which includes pellets of the oxidizing composition which permits the timed release of potassium and/or sodium permanganate in the moving substantially aqueous stream.
Sewage treatment stations or streams which contain waste materials such as hydrogen sulfide or acid mine drainage which includes iron and manganese often are in remote areas or are in areas without adequate utilities such as power and water. This makes the use of chemical feed equipment impractical or impossible. The lack of adequate utilities, however, does not stop the need to treat streams having deleterious waste materials. These waste materials may be controlled through an oxidation reaction between sodium or potassium permanganate and hydrogen sulfide or the iron or manganese compounds in acid mine drainage. With electromechanical metering equipment, the permanganate may be added to the water containing the waste which is to be oxidized. But without adequate power or water immediately available, this equipment cannot be used.
Timed or controlled release of potassium or sodium permanganate into the waste water stream would provide a solution to providing permanganate to oxidize waste. Known products for the timed release of permanganate do not solve the problem of metering sufficient permanganate into a stream to oxidize waste such as hydrogen sulfide and thereby reduce the noxious odor of that gas into the environment. U.S. Pat. Nos. 5,152,804 and 4,961,751 to Eissale et al. describe cement pellets which include permanganate crystals distributed in a cured hydrated mineral cement such as gypsum, Sorel cement, Portland cement and Pozzolan cement. These patents describe using these permanganate cement pellets as xe2x80x9cfrosting stonesxe2x80x9d for bleaching denim garments where the action of the stones on the garments provided the garments with a xe2x80x9cusedxe2x80x9d or xe2x80x9cfrostedxe2x80x9d style. The stones abrade against the garment as well as other stones as the damp garments would be tumbled with the stones to bleach and abrade the garment. These cement stones are too hard and resistant to disintegration to provide a proper timed release of permanganate in a water stream. U.S. Pat. No. 5,261,924 to Reidies et al. describes a layered composition with a hardened core and a cement outer layer. The core in the product of the ""924 patent includes permanganate, a hydrated cement or a hardened binder/clay combination. The outer layer has Sorel cement or gypsum. While the patent describes a binder/clay combination, that combination is only an inner core of a pellet. The core of the pellet is encased in a very hard cement outer layer of Sorel cement or gypsum. Again this product is too hard and resistant to disintegration to provide a proper timed release of permanganate in a water stream. U.S. Pat. No. 5,273,547 to Reidies describes pellets of Sorel cement with permanganate distributed at the core, but not at the surface of the pellets. This product, as with the products described in the other patents described herein, is too hard and resistant to disintegration to provide a proper timed release of permanganate in a water system for the oxidative destruction of waste such as H2S.
It is an object of the invention to provide an oxidizing product which will provide a proper timed release of permanganate into a moving aqueous stream to oxidize undesired materials in the stream.
It is another object of the invention to provide a kit for use in controlling undesired materials and for providing the timed release of permanganate in an aqueous stream.
It is yet another object of the invention to provide a method for controlling undesired materials and provide the timed release of permanganate in an aqueous stream.
These and other objects of the invention will become apparent upon reference to the specification herein.
This invention is directed to an oxidizing composition of agglutinated particles comprising an alkali metal permanganate, a binder/coating agent of an alkali metal silicate and/or alkali metal aluminate and a filler such as clay, diatomaceous earth, talc, ground silica or zeolites. This invention also is directed to an oxidizing kit which includes a pervious container and the oxidizing composition. This invention also is directed to a method of oxidizing waste materials with the kit in a substantially aqueous moving fluid stream. The oxidizing composition is uniquely composed of small pellets, briquettes or other agglutinated masses or particles such that when a plurality of the particles are in a pervious container which container is in a moving substantially aqueous stream, the particles will slowly disintegrate and release the permanganate over time in the stream. With the disintergration of the product, no residual carrier of the permanganate is left to create a disposal problem. The released permanganate will oxidize waste materials in the stream such as hydrogen sulfide, or will oxidize iron and/or manganese in acid mine drainage. Further, the invention includes a method of reducing materials, especially undesired effluent materials in a substantially aqueous moving fluid stream.
According to the method of the invention, the container of the kit holds a plurality of pellets of the oxidizing composition and is put into the moving stream which carries the material which is to be oxidized by the alkali metal permanganate in the pellets. The moving stream moves the pellets in the container against each other and abrades the surface of the pellets sufficiently such than manganese dioxide will not form on the pellet surface and inhibit the oxidation reaction of the permanganate and the material in the stream being oxidized. The abrasion and moving action of the stream is effective for disintegration of the pellets and provides timed release of the particulate permanganate in the moving stream. The plurality of pellets, pellet size and surface area, the balance between amounts of alkali metal permanganate, binder/coating agent and filler in the pellet, the speed of the moving stream and the substantially aqueous environment all combine to provide a suitable disintegration of the pellet and the timed release rate of permanganate to effect the oxidation reaction.
The oxidizing composition comprises agglutinated particles or pellets comprising from about 60 to about 80 weight percent sodium or potassium permanganate distributed throughout the pellets which also comprise from about 10 to about 20 weight percent of a binder/coating agent which is an alkali metal silicate and/or alkali metal aluminate and from about 10 to about 20 weight percent of a filler. In an important aspect, the pellets or agglutinated particles have a size of from about xc2xc inches to about 2 inches in diameter and are about 1 to about 3 inches long. In another important aspect, the amounts of sodium or potassium permanganate, binder/coating agent and filler clay are balanced with pellet size and number of pellets such that when a plurality of pellets are at least partially immersed in a substantially aqueous moving stream from about 0.5 to about 10 pounds of permanganate will be delivered into the aqueous environment to oxidize materials therein. In another important aspect, the binder/coating agent is sodium silicate also known as water glass.
The kit of the invention comprises the agglutinated pellets and a pervious container which is not reactive with the sodium or potassium permanganate or the waste material to be oxidized in the aqueous stream. The container may be a walled container with holes or a bag with holes or made of mesh or a net which holes or net permits the flow of the substantially aqueous stream through the container to contact, move, disintegrate the pellets, dissolve the permanganate and time release the permanganate in the aqueous environment at a rate of from about 0.5 to about 10 pound of sodium and/or potassium permanganate per day. In an important aspect, the container is a flexible mesh bag made of a material such as polyester which will not decompose in an aqueous permanganate environment, as contemplated by the timed release of permanganate and permanganate concentrations described herein, and which permits movement of the pellets in an aqueous stream. In another important aspect, where waste water containing hydrogen sulfide is treated, the composition and the size of the pellets should be balanced to effect from about 4 to about 9 pounds of sodium and/or potassium permanganate per day, and in a very important aspect, from about 6 to about 8 pounds of sodium and/or potassium permanganate per day.
Definitions
xe2x80x9cPelletxe2x80x9d or xe2x80x9cpelletsxe2x80x9d means any agglutinated mass or masses which may be spherical, cylindrical or pillow shaped which may be pelletized through extrusion, which may be briquetted or otherwise agglomerated or molded.
xe2x80x9cNon-layered pelletxe2x80x9d means a pellet which has sodium permanganate or potassium permanganate distributed throughout the pellet in a generally random way where the permanganate is not concentrated in one volume part of the pellet, such as a layer near the surface of the pellet.
xe2x80x9cNon-reactive containerxe2x80x9d means a container made of or coated with a material which does not react with permanganate such as polyethylene, polypropylene, chlorinated polyvinyl chloride, polyvinyl chloride or polyester.
xe2x80x9cClayxe2x80x9d means natural mineral mixtures based upon silica and alumina such as bentonite and attapulgite clay.
xe2x80x9cSubstantially aqueousxe2x80x9d means a liquid material which comprises at least 70 weight percent water.
xe2x80x9cAlkali metal aluminatexe2x80x9d means sodium and/or potassium aluminates.
xe2x80x9cAlkali metal silicatexe2x80x9d means sodium and/or potassium silicate.